2 answers

If you hover over the three dots to the right of the Future Sprint you can see the SprintId showing on the Browser status bar. Note, the full url showing is not useful as it returns JSON.

It would be great if one could build a url which would open the Backlog with all sprint collapsed except the one you want expanded, but there is no way to do that. I opened an issue for this: JRASERVER-66960

The only alternative to get a url for each sprint is to save the individual queries for each sprint to their own filterid.

...It's true that there are projects in Jira; but they are merely a way to cut off issues, to tell them apart from other sections of work and to apply rules that are specific to that team (the schemes)....